Project Summary Less than half of COPD patients receive the care recommended by practice guidelines. In an era of accountable care organizations and value-based purchasing, there has been increased focus on the patient and system level factors that contribute to the delivery of high quality care and outcomes of patients with chronic conditions such as COPD. With this increased focus has come a recognition that the ?complexity? of both patients and health care systems likely contribute to failures in healthcare delivery, but the extent to which this occurs is not known. Patients with COPD are often described as complex, which has historically been equated to having multiple comorbidities. Recently, there is increased recognition that complexity goes beyond medical comorbidities and includes many social determinants of health that impact patient outcomes. This patient complexity can affect behaviors such as adherence to medications, and the ability to navigate a healthcare system that is also becoming increasingly complex. As patients and systems become more complex, the number of opportunities for failures in healthcare delivery likely increases. Targeting better organization of the structure and processes behind high-quality healthcare delivery may improve outcomes for patients with COPD. To date, it is unknown how patient and health system complexity affects care quality in the management of COPD, but may help explain the larger gaps in care delivery and treatment relative to other common chronic illnesses, such as heart failure. The overarching goal of this training proposal is to examine how patient and health system complexity affects quality of care and medication adherence for patients with COPD. We hypothesize that as both patient and health system complexity increases the delivery of high quality care and adherence decrease. If our hypotheses are true, the results of this study may provide a basis to develop systems to facilitate care services and improve the quality of care delivered to complex patients with COPD.